add flags to permissions groups

Flags can be added to permissions group to store some metadata.

An interface `PermissionsGroupFlagProvider` allow to add some flag to the form which create/
edit permissions groups.

DependencyInjection/CompilerPass/ACLFlagsCompilerPass.php

@@ -0,0 +1,39 @@
+<?php
+/*
+ */
+namespace Chill\MainBundle\DependencyInjection\CompilerPass;
+
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Chill\MainBundle\Form\PermissionsGroupType;
+use Symfony\Component\DependencyInjection\Reference;
+
+/**
+ * 
+ *
+ * @author Julien Fastré <julien.fastre@champs-libres.coop>
+ */
+class ACLFlagsCompilerPass implements CompilerPassInterface
+{
+    public function process(ContainerBuilder $container)
+    {
+        $permissionGroupType = $container->getDefinition(PermissionsGroupType::class);
+        
+        foreach($container->findTaggedServiceIds('chill_main.flags') as $id => $tags) {
+            $reference = new Reference($id);
+            
+            foreach ($tags as $tag) {
+                switch($tag['scope']) {
+                    case PermissionsGroupType::FLAG_SCOPE:
+                        
+                        $permissionGroupType->addMethodCall('addFlagProvider', [ $reference ]);
+                        break;
+                    default:
+                        throw new \LogicalException(sprintf(
+                            "This tag 'scope' is not implemented: %s, on service with id %s", $tag['scope'], $id)
+                            );
+                }
+            }
+        }
+    }
+}